forgejo/vendor/github.com/djherbis/buffer/limio/limit.go

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package limio
import "io"
type limitedWriter struct {
W io.Writer
N int64
}
func (l *limitedWriter) Write(p []byte) (n int, err error) {
if l.N <= 0 {
return 0, io.ErrShortWrite
}
if int64(len(p)) > l.N {
p = p[0:l.N]
err = io.ErrShortWrite
}
n, er := l.W.Write(p)
if er != nil {
err = er
}
l.N -= int64(n)
return n, err
}
// LimitWriter works like io.LimitReader. It writes at most n bytes
// to the underlying Writer. It returns io.ErrShortWrite if more than n
// bytes are attempted to be written.
func LimitWriter(w io.Writer, n int64) io.Writer {
return &limitedWriter{W: w, N: n}
}